Sampling head remove/install with scope power on?


 

Is it safe to remove or install an S-1 through S-6 sampling head from its plug-in without turning off the scope?

There is nothing mentioned in the manuals for the various heads (or plugins, like my 3S2)... in the pictures I can see that one pin on each side of the head's edge fingers is shorter than the others. I would have thought that Tek would provide a warning - or maybe it's just something that engineers in the 60's assumed?

It's hard on the scope to keep turning it on and off, but I don't want to blow up my heads either.
Thoughts?


Stephen Hanselman
 

No matter what a “book” might say hot-plugging any active electronic device is at best a crap-shoot and more likely a very bad idea.

Regards,

Stephen Hanselman
Datagate Systems, LLC

On Mar 31, 2021, at 10:05, Charles <charlesmorris800@centurytel.net> wrote:

Is it safe to remove or install an S-1 through S-6 sampling head from its plug-in without turning off the scope?

There is nothing mentioned in the manuals for the various heads (or plugins, like my 3S2)... in the pictures I can see that one pin on each side of the head's edge fingers is shorter than the others. I would have thought that Tek would provide a warning - or maybe it's just something that engineers in the 60's assumed?

It's hard on the scope to keep turning it on and off, but I don't want to blow up my heads either.
Thoughts?





 

True, unless specifically designed for it, which is why I asked.


Tom Lee
 

If the manual does not say specifically that hot-plugging is supported, assume that it is not.

Sent from my iThing, so please forgive typos and brevity.

On Mar 31, 2021, at 12:56 PM, Charles <charlesmorris800@centurytel.net> wrote:

True, unless specifically designed for it, which is why I asked.





Albert Otten
 

S-2 Ceck and Recal procedure.
Step 2a, remove the extender cable from the sampling head: " ... the oscilloscope power may be left on".
Step 2c: reconnect, no remarks about power.
I prefer to go for safety.
Albert


 

Thanks Albert. I KNEW I had seen that phrase somewhere in all my manuals, just couldn't find it! :)
I've been hot-swapping them, at least the S-1 and S-2, multiple times without incident.
In fact, I've inadvertently pulled them more than once because I forgot to set the lock, and those GR connectors are stiff.

Anyhow, I agree that it's better to err on the side of caution.
(The S-4 is safely in its antistatic bag with an SMA shorting plug installed, where it will sit until I get a Leo Bodnar pulser to check its risetime. It is now no longer repairable since there is no source of replacement diode hybrids).


Roger M
 

I would bet my bottom dollar that the issue of hot plugging a sampling head
was discussed by its designers and would have been documented as a
no-no (or blocked by some mechanism) if there was chance of failure.

Still, one may think of hot plugging as a "bad idea", much like::
- playing with elemental mercury as a kid
- sanding lead based paint
- swimming right after eating
- waiting over 5K miles to change your oil
- "floating" a scope
- ripping up your asbestos laced flooring
- looking into a laser with your good eye
- putting down your beer, and saying "here,... watch this..."
-Roger


 

Roger M wrote:
Still, one may think of hot plugging as a "bad idea", much like:
...
- putting down your beer, and saying "here,... watch this..."
Which is, of course, why you always ask someone else to hold your beer

-- Jeff Dutky


Harvey White
 

Or is it much smarter to hold their beer for them.....?

Harvey

On 4/1/2021 9:02 PM, Jeff Dutky wrote:
Roger M wrote:
Still, one may think of hot plugging as a "bad idea", much like:
...
- putting down your beer, and saying "here,... watch this..."
Which is, of course, why you always ask someone else to hold your beer

-- Jeff Dutky





 

"I'll hold your beer" should be the new highly-coded put down